Field of the invention
[0001] The present invention relates to a new probiotic with immune modulating properties.
Background of the invention
[0002] During recent years it has become generally accepted that adequate function of the
human immune system depends on the complex interaction of the microbiota with the
human mucosa (Belkaid et al., 2014; Cao et al., 2014). In normal health, nonpathogenic
bacteria activate the immune system to induce tolerance to microbiota essential for
energy harvesting and immune development (de Kivit et al., 2014; Geuking et al., 2014;
Walker et al., 2014). However, under specific conditions immune responses may occur
against microbes that contribute to the development of diseases such as IBD (Meijerink
et al., 2010). Human health may benefit from more insight in how microorganisms contribute
to homeostasis of immune responses and how they prevent inflammation. The hope is
it will lead to design of tailored interventions.
[0003] Commensal
Lactobacilli species may play an active role in the maintenance of homeostasis of immune responses
by guiding the polarization of T-cells toward regulatory T (Treg) cells and suppression
of allergy associated Th2 responses (Smelt et al., 2013). This is considered to be
accomplished by the interactions of bacterial cell wall components or secreted bacterial
products that interact with immune or epithelial cells in the human mucosa (Walker
et al., 2014). These interactions however seem to contribute to more than just tolerance
to the beneficial microbes. In many studies
Lactobacilli have been shown to have a positive impact on immune responses as shown in several
vaccination studies (Meijerink et al., 2012; Wells et al., 2011). Also,
Lactobacilli activate more general tolerogenic cellular pathways in humans as recently shown (van
Baarlen et al., 2010; van Baarlen et al., 2009).
[0004] Lactobacillus plantarum is a well characterized food-derived bacterium (van Baarlen et al., 2009). In previous
studies it has been shown that
Lactobacillus plantarum strains have different effects on human dendritic cells and human peripheral blood
mononuclear cells (Meijerink et al., 2010; Meijerink et al., 2012; Wells et al., 2011;
van Baarlen et al., 2010; van Baarlen et al., 2009; Van Hemert et al., 2010). By applying
comparative genome hybridization a number of bacteriocins and cell-wall components
involved in glycosylation of cell wall teichoic acids have been identified that are
associated with these differential effects (Meijerink et al., 2010; Meijerink et al.,
2012; Wells et al., 2011; van Baarlen et al., 2010; van Baarlen et al., 2009; Van
Hemert et al., 2010; Smet et al., 2013). It is assumed that this differential expression
of
Lactobacillus plantarum genes contributes to the observed differences in activation of Toll-like receptor
(TLR)2-4, CD14 antigens, and nucleotide-binding oligomerization domain-containing
2 (NOD2) (Meijerink et al., 2010). As a consequence of differences in TLR-binding,
Lactobacillus plantarum strains induce upon incubation with monocytes or dendritic cells different quantities
of the proinflammatory cytokine IL12 and the regulatory cytokine IL10 (Meijerink et
al., 2010; Meijerink et al., 2012; Wells et al., 2011; van Baarlen et al., 2010; van
Baarlen et al., 2009; Van Hemert et al., 2010; Smet et al., 2013; Smelt et al., 2013).
The gastrointestinal barrier may be disrupted on almost a daily basis by e.g. nonsteroidal
anti-inflammatory drugs (NAISDs), sports or alcohol intake and as such cause (mild)
inflammation of the intestine. A mild stressor cytokine that is very common in the
Western society is the consumption of an NSAID such as indomethacin. Millions are
using NSAIDs for the treatment of musculoskeletal pain. A side effect of these NSAIDs
is the mild inflammation of the intestine by disruption of the gastrointestinal immune
barrier (Schoultz et al., 2012). As NSAIDs are used by millions worldwide there is
an urgent need to treat such (mild) inflammation of the intestine.
[0005] Another issue where food derived antigens may play a role is in maintaining vaccination
efficacy. It is well known that immune memory to an antigen encountered in past (some
decades ago) may wane over time. When the individual encounters the antigen or pathogen
associated with the antigen again, such waned immune memory may result in an insufficient
response to the antigen or pathogen associated with the antigen (Deasy et al., 2013;
Kerneis et al., 2014; Poorolajal et al., 2010; Schure et al., 2012).
CN-A-102 747 012 disclosse a probiotic formulation comprising a Lactobacillus plantarum P8 strain.
Accordingly, there is an urgent need to preserve, maintain and/or reactivate the immune
memory. This could not only revive a waned immune response, it could also render the
host immune system more susceptible to vaccination protocols, which may be specifically
beneficial for immune compromised individuals such as elderly. In addition, to identify
and to demonstrate effects of immune modulating products, adequate biomarkers and
assays are lacking. Accordingly, there is an urgent need for such biomarker and/or
assay.
Description of the invention
[0006] Surprisingly, it has now been demonstrated that a specific
Lactobacillus has immune modulating properties. Such specific
Lactobacillus preferably also has anti-inflammatory properties.
[0007] Accordingly, in a first aspect the present invention provides a probiotic formulation
comprising at least one food-grade substance and at least one probiotic bacterial
strain which has at least 50% sequence identity with the genome of
Lactobacillus plantarum TIFN 101 (deposited under number CBS 138100 at the Centraalbureau voor Schimmelcultures,
Uppsalalaan 8, 3584 CT The Netherlands). Said probiotic formulation is herein referred
to as a probiotic formulation according to the present invention. Said probiotic bacterial
strain is herein referred to as a probiotic bacterial strain according to the present
invention and has immune modulating properties and preferably also has anti-inflammatory
properties.
[0008] Outside the scope of the claimed invention, a preferred probiotic bacterial strain
comprises at least one polynucleotide that has at least 50% sequence identity with
a polynucleotide sequence selected from the group consisting of SEQ ID NO: 1 - SEQ
ID NO: 174. Preferably, a probiotic bacterial strain comprises at least two, more
preferably three, four, five, six, seven, eight, nine, ten, twenty, thirty, forty,
fifty, sixty, seventy, eighty, ninety or most preferably hundred polynucleotides that
each have at least 50% sequence identity with a polynucleotide sequence selected from
the group consisting of SEQ ID NO: 1 - SEQ ID NO: 174.
[0009] A further preferred probiotic bacterial strain comprises at least one polynucleotide
that has at least 50% sequence identity with a polynucleotide sequence selected from
the group consisting of SEQ ID NO: 176 - SEQ ID NO: 256. Preferably, a probiotic bacterial
strain comprises at least two, more preferably three, four, five, six, seven, eight,
nine, ten, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety or most preferably
hundred polynucleotides that each have at least 50% sequence identity with a polynucleotide
sequence selected from the group consisting of SEQ ID NO: 176 - SEQ ID NO: 256.
[0010] A further preferred probiotic bacterial strain comprises at least one polynucleotide
that has at least 50% sequence identity with a polynucleotide encoding a polypeptide
with a sequence selected from the group consisting of SEQ ID NO: 260 - SEQ ID NO:
340. Preferably, a probiotic bacterial strain according to the present invention comprises
at least two, more preferably three, four, five, six, seven, eight, nine, ten, twenty,
thirty, forty, fifty, sixty, seventy, eighty, ninety or most preferably hundred polynucleotides
that each have at least 50% sequence identity with a polynucleotide encoding a polypeptide
with a sequence selected from the group consisting of SEQ ID NO: 260 - SEQ ID NO:
340.
[0011] The immune modulating properties can be assessed
in vivo and
in vitro. For a preferred assessment
in vitro, Peripheral Blood Mononuclear Cells (PBMC) are isolated from blood and stimulated
with an antigen and the probiotic bacterial strain or a part or an extract thereof.
[0012] An immune modulating property of the probiotic bacterial strain according to the
present invention preferably is the ability to preserve, maintain and/or reactivate
an immune response raised by a previous immunization and is preferably defined as
the ability to maintain or increase the amount of a sub-population of PBMC within
a population of PBMC. Preferably said sub-population is an antigen specific CD45RO+
population, preferably selected from CD3+/CD4+/CD45RO+ cells (memory Thelper cells),
CD3+/CD4+/CD45RO+/CD69+ cells (activated memory Thelper cells), CD3+/CD8+/CD45RO+
cells (cytotoxic T cells), CD3+/CD8+/CD45RO+/CD69+ cells (activated memory T cells),
CD3+/CD4+/CD45RO+/CCR7+/CD62L+ cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L-
cells (effecter memory Thelper cells). Further preferred sub-populations are CD3+/CD4+/Foxp3+
cells (Foxp3+ Thelper cells), and IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells
(IFNγ and/or IL17 producing memory Thelper cells). Preferably, the sub-population
of CD3+/CD4+/Foxp3+ cells (Foxp3+ Thelper cells) and/or CD3+/CD8+/CD45RO+/CD69+ cells
(activated memory T cells) are maintained in a subject that is administered a probiotic
formulation or the probiotic bacterial strain according to the present invention.
Preferably, the sub-population of IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells
(IFNγ and/or IL17 producing memory Thelper cells) is increased in a subject that is
administered a probiotic formulation or the probiotic bacterial strain according to
the present invention.
[0013] Preferably, the antigen is a recall antigen by purposive or non-purposive immunization,
i.e. an antigen that the individual has encountered previously; more preferably, the
recall antigen is selected from the group consisting of tetanus toxin, Hepatitis B
antigen and Influenza. Preferably, an increase in the amount of the specific sub-population
of PBMC is at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% (i.e. a 1-fold
increase), a 2-fold increase, a 3-fold increase, a 4-fold increase, a 6-fold increase,
a 10-fold increase, a 50-fold increase, a 100-fold increase, a 1000-fold increase,
or at least a 10.000-fold increase. Such increase can be measured by any assay known
by the person skilled in the art and is preferably measured with an assay as described
herein.
[0014] A further preferred immune modulating property is enhanced cytokine production of
memory Thelper cells, more preferably activated memory Thelper cells; preferably the
percentage of IL-17- producing (activated) memory Th cells and/or the percentage of
IFNγ-producing (activated) memory Th cells is/are increased compared to a control
that has no probiotic according to the present invention administered. The increase
in percentage is preferably at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%,
100% (i.e. a 1-fold increase), a 2-fold increase, a 3-fold increase, a 4-fold increase,
a 6-fold increase, a 10-fold increase, a 50-fold increase.
[0015] A further preferred immune modulating property of a probiotic formulation or a probiotic
bacterial strain according to the present invention is the induction of a change in
IL10/IL12 ratio by dendritic cells when assayed according to Meijerink et al., 2010,
preferably a change into a relatively high IL10/IL12 ratio. The increase in ratio
is preferably at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% (i.e. a 1-fold
increase), a 2-fold increase, a 3-fold increase, a 4-fold increase, a 6-fold increase,
a 10-fold increase, a 50-fold increase.
[0016] A further preferred immune modulating property is the induction of a differential
transcriptional response in duodenal mucosa. Preferably, a gene encoding a compound
selected from the group consisting of immunoglobulin lambda variable 6-57, putative
V-set and immunoglobulin domain-containing protein 6-like, immunoglobulin lambda variable
7-46, interferon regulatory factor 4, GDNF family, CD27, CD79a, and plasminogen activator
is upregulated. The upregulation is preferably an increase of expression level of
at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% (i.e. a 1-fold increase),
a 2-fold increase, a 3-fold increase, a 4-fold increase, a 6-fold increase, a 10-fold
increase, a 50-fold increase.
[0017] A further preferred immune modulating property is the upregulation of MHC-II α in
the duodenal mucosa. The upregulation is preferably an increase of at least 10%, 20%,
30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% (i.e. a 1-fold increase), a 2-fold increase,
a 3-fold increase, a 4-fold increase, a 6-fold increase, a 10-fold increase, a 50-fold
increase. The immune modulating properties can be combined properties of the probiotic
bacterial strain according to the present invention.
[0018] A probiotic formulation may comprise at least one further bacterial strain, which
is preferably a probiotic bacterial strain.
[0019] A probiotic formulation according to the present invention comprises at least the
probiotic bacterial strain according to the present invention and at least one food-grade
substance. A food-grade substance is herein further referred to as a food-grade substance
according to the present invention and is a substance suitable for consumption by
a subject, preferably a human or an animal, more preferably a human. A food-grade
substance may be of plant or animal origin, and may contain essential nutrients, such
as carbohydrates, fats, proteins, vitamins, and/or minerals. A food-grade substance
may be intended for ingestion by an organism and subsequently assimilation by the
organism's cells to produce energy, maintain life, and/or stimulate growth. A food-grade
substance according to the present invention includes but is not limited to a substance
selected from the group consisting of a dairy-, grain-, vegetable-, fruit-, fish-,
or meat- based product. The term "based product" is herein defined that the food-grade
substance is produced from a specific raw material such as dairy, grain, vegetable,
fruit, fish, or meat. The food-grade substance may be based on a mixture of different
raw materials e.g. a mixture of dairy and grain or a mixture of meat and fruit.
[0020] A probiotic bacterial strain may be any probiotic bacterial strain. Probiotics are
live microorganisms which, when administered in adequate amounts, confer a health
benefit on the host (FAO/WHO,
Evaluation of health and nutritional properties of powder milk with live lactic acid
bacteria. Report of FAO/WHO expert consultation 1-4 October. 2001). The most widely applied probiotics belong to the genera
Lactobacillus and
Bifidobacterium (Marco et al., 2006). Their beneficial effects are exerted via several mechanisms,
including the modulation of the intestinal microbiota, the production of antibacterial
substances, improvement of epithelial barrier function, and reduction of intestinal
inflammation (Corr, et al., 2009; Saulnier et al., 2009; Saxelin et al., 2005). Probiotics
are most commonly provided through ingestion of freshly fermented food products or
dried bacterial preparations. The viability of probiotic strains is considered an
important trait for probiotic functionality; reaching their side of action in the
intestine alive is thus considered an important trait for probiotic strains (Ma et
al., 2004; Gobbetti et al., 2010). The present invention employs a further probiotic
bacterial strain. A preferred further probiotic bacterial strain according to the
present invention is a bacterial strain selected from the group consisting of the
genera of
Lactobacillus, Lactococcus, Leuconostoc, Carnobacterium, Streptococcus, Bifidobacterium,
Bacteroides, Eubacterium, Clostridium, Fusobacterium, Propionibacterium, Enterococcus,
Staphylococcus, Peptostreptococcus, and
Escherichia, preferably consisting of
Lactobacillus and
Bifidobacterium. Preferred species of
Lactobacillus, Bifidobacterium, Streptococcus, Leuconostoc and
Pediococcus. are
Lactobacillus reuteri, L. fermentum, L. acidophilus, L. crispatus, L. gasseri, L.
johnsonii, L. plantarum, L. paracasei, L. murinus, L. jensenii, L. salivarius, L.
minutis, L. brevis, L. gallinarum, L. amylovorus, Streptococcus thermophilus, Leuconostoc
mesenteroides, Pediococcus damnosus, P. acidilactici, P. parvulus, Bifidobacterium
bifidum, B. longum, B. infantis, B. breve, B. adolescente, B. animalis, B. gallinarum,
B. magnum, and B. thermophilum. The
Lactobacillus bacterium is preferably
Lactobacillus plantarum, more preferably a
Lactobacillus plantarum from the group consisting of
Lactobacillus plantarum JDM1, ST-III, F9UP33, EITR17, D7V971 (ATCC14917) and C6VQ24, even more preferably
Lactobacillus plantarum WCFS1.
[0021] It is understood that replicates of the deposited strain according to the present
invention is encompassed by the invention. The term "replicate" refers to the biological
material that represents a substantially unmodified copy of the material, such as
material produced by growth of micro-organisms, e.g. growth of bacteria in culture
media.
[0022] Preferably, in a probiotic formulation according to the present invention, the concentration
of probiotic bacterial strains ranges from about 1 to about 99 weight percent, more
preferably from about 5 to about 90 weight percent, more preferably from about 5 to
about 80, more preferably from about 5 to about 70, more preferably from about 5 to
about 60, more preferably from about 10, 20, 30, or 40 to about 50 weight percent
with respect to the total weight of the formulation, and/or about 1 E+4, 1 E+5, or
1 E+6 to about 1 E+8, 1 E+9, 1 E+10, 1 E+11, or 1 E+12 colony forming units/ml of
formulation, even more preferably about 1x10 E+6 to about 1x10 E+12 colony forming
units/ml of formulation.
[0023] More preferably, in a probiotic formulation according to the present invention, the
concentration of probiotic bacterial strains ranges from 1 to 99 weight percent, more
preferably from 5 to 90 weight percent, more preferably from 5 to 80, more preferably
from 5 to 70, more preferably from 5 to 60, more preferably from 10, 20, 30, or 40
to 50 weight percent with respect to the total weight of the formulation, and/or 1
E+4, 1 E+5, or 1 E+6 to 1 E+8, 1 E+9, 1 E+10, 1 E+11, or 1 E+12 colony forming units/ml
of formulation, even more preferably 1x10 E+6 to 1x10 E+12 colony forming units/ml
of formulation. A colony forming unit is a term known to the person skilled in the
art and one unit typically refers to the amount of bacteria that forms one colony
on a culture plate; it is a term to refer to viable bacteria.
[0024] Even more preferably, in a probiotic formulation according to the present invention,
the concentration of probiotic bacterial strains ranges from about 10 to about 50
weight percent with respect to the total weight of the formulation and/or about 1
E+6 to about 1 E+12 colony forming units/ml of formulation.
[0025] The probiotic formulation or a probiotic bacterial strain according to the present
invention may be in any form or state of constitution known to the person skilled
in the art. The probiotic formulation or a probiotic bacterial strain according to
the present invention may be part of a (compressed) tablet or pill or may be contained
within another vehicle such as a container or a capsule, a gel, or a drop. A preferred
vehicle is a container with a liquid volume between 0.5 and 50 ml suitable for comprising,
preferably comprising a probiotic formulation or a probiotic bacterial strain according
to the present invention.
[0026] The probiotic formulation or a probiotic bacterial strain according to the present
invention may also conveniently be comprised in a food substance. Accordingly, in
a second aspect, the present invention provides for a food product, a formulation
for food enrichment, a food supplement, a nutraceutical formulation or a pharmaceutical
formulation comprising a probiotic formulation or a probiotic bacterial strain according
to the present invention. A food product according to the present invention is preferably
a food-grade substance as described previously herein.
[0027] A food, food composition, nutraceutical formulation, formulation for food enrichment,
food supplement and pharmaceutical formulation according to the present invention
is herein understood to include liquids for human or animal consumption, i.e. a drink
or beverage. The food, food composition, nutraceutical formulation, formulation for
food enrichment, food supplement and pharmaceutical formulation may be a solid, semi-solid,
semi-liquid and/or liquid food or food substance, and in particular may be a dairy
product, such as a fermented dairy product, including but not limited to a yoghurt,
a yoghurt-based drink, a yoghurt-like drink, a cheese or a buttermilk. Such foods
may be prepared in a manner known per se, e.g. by adding a probiotic formulation or
a probiotic bacterial strain according to the present invention to a suitable food
or food-grade substance, in a suitable amount. In doing so, probiotic formulation
or a probiotic bacterial strain according to the present invention may be used in
a manner known per se for the preparation of such (fermented) food or food-grade substance,
e.g. in a manner known per se for the preparation of fermented dairy products using
a probiotic formulation or a probiotic bacterial strain according to the present invention.
In such methods, a probiotic formulation or a probiotic bacterial strain according
to the present invention may be used in addition to the micro-organism usually used,
and/or may replace one or more or part of the micro-organism usually used. For example,
in the preparation of fermented dairy products such as yoghurt or yoghurt-based drinks,
a probiotic formulation or a probiotic bacterial strain according to the present invention
may be added to or used as part of a starter culture or may be suitably added during
such a fermentation.
[0028] A pharmaceutical formulation (or pharmaceutical composition) comprising a probiotic
formulation or a probiotic bacterial strain according to the present invention may
be for human or animal usage in human and veterinary medicine, particularly for human
therapy, and comprises at least a probiotic formulation or a probiotic bacterial strain
according to the present invention and a pharmaceutically accepted excipient. The
pharmaceutically accepted excipient may be any such excipient known to the person
skilled in the art such as a pharmaceutically or nutritionally acceptable carrier
or diluent. Examples of such suitable excipient for a pharmaceutical formulation described
herein may be found in the "
Handbook of Pharmaceutical Excipients", 2nd Edition, (1994), Edited by A Wade and
PJ Weller and in "
Remington's Pharmaceutical Sciences", Mack Publishing Co. (A. R. Gennaro edit. 1985). Examples of suitable carriers include lactose, starch, glucose, methyl cellulose,
magnesium stearate, mannitol, sorbitol and the like. Examples of suitable diluents
include saline, glycerol, water and mixtures thereof.
[0029] A food, food composition, nutraceutical formulation, formulation for food enrichment,
food supplement and pharmaceutical formulation according to the present invention
is preferably present in a container with a liquid volume between 0.5 and 1000 ml.
Accordingly, the present invention provides for a container with a liquid volume between
0.5 and 1000 ml comprising a food, food composition, nutraceutical formulation, formulation
for food enrichment, food supplement and pharmaceutical formulation according to the
present invention.
[0030] The probiotic formulation according to the present invention and/or a probiotic bacterial
strain comprising
Lactobacillus plantarum TIFN 101, can conveniently be used as a medicament, preferably for the treatment
or prevention of intestinal inflammation.
[0031] Accordingly, in a third aspect the present invention provides for the probiotic bacterial
strain according to the present invention, and/or a probiotic formulation or a pharmaceutical
formulation according to the present invention, preferably as defined in the first
and/or second aspect of the present invention, for use as a medicament, preferably
in the treatment or prevention of intestinal inflammation.
[0032] The present disclosure also provides for a method of treatment of intestinal inflammation
or a method prevention of intestinal inflammation comprising administration of the
probiotic bacterial strain according to the present invention, and/or a probiotic
formulation or a pharmaceutical formulation according to the present invention, preferably
as defined in the first and/or second aspect of the present invention.
[0033] Intestinal inflammation within the scope of the present invention may be any intestinal
inflammation known to the person skilled in the art, such as but not limited to inflammation
caused by nonsteroidal anti-inflammatory drugs (NAISDs), sports, alcohol intake, irritable
bowel syndrome, allergy, celiac disease, inflammatory bowel disease, Crohn's disease,
gastrointestinal related autoimmune diseases such as Type I diabetes.
[0034] The probiotic formulation according to the present invention and/or the probiotic
bacterial strain according to the present invention, can conveniently be used for
modulation of the immune system, wherein modulation of the immune system is preferably
as described previously herein. Accordingly, in a fourth aspect, the present invention
provides for the probiotic bacterial strain according to the present invention, and/or
a probiotic formulation according to the present invention or a pharmaceutical formulation
according to the present invention for use as a medicament comprising administration
of an effective amount of the probiotic bacterial strain according to the present
invention and/or of the probiotic formulation or a pharmaceutical formulation according
to the present invention for modulating the immune system, wherein modulation of the
immune system is preferably as described previously herein.
[0035] The present disclosure also also provides for a method of modulating the immune system
of a subject suffering from intestinal inflammation, comprising administration to
said subject an effective amount of the probiotic bacterial strain according to the
present invention and/or an effective amount a probiotic formulation according to
the present invention or a pharmaceutical composition according to the present invention.
[0036] Preferably, in this aspect of the present invention, an effective amount is about
1 E+4, 1 E+5, or 1 E+6 to about 1 E+8, 1 E+9, 1 E+10, 1 E+11, or 1 E+12 colony forming
units/ml of formulation, more preferably about 1x10 E+6 to about 1x10 E+12 colony
forming units/ml of formulation. More preferably, an effective amount is 1 E+4, 1
E+5, or 1 E+6 to 1 E+8, 1 E+9, 1 E+10, 1 E+11, or 1 E+12 colony forming units/ml of
formulation, even more preferably 1x10 E+6 to 1x10 E+12 colony forming units/ml of
formulation.
[0037] Preferably, modulation of the immune system according to this aspect comprises maintenance
and/or reactivation of an immune response raised by a previous immunization and/or
enhancing memory T-cells generated previously by immunization, as described previously
herein.
[0038] To identify and to demonstrate the effects of immune modulating products such as
described in the previous aspects of the present invention, adequate biomarkers and
assays are presented herein.
[0039] Provided is a method for the detection of a response to an agent comprising:
- a. stimulating PBMC from a sample of a subject with at least one antigen,
- b. identifying a sub-population of PBMC,
- c. comparing the data from (b) to data of a, preferably otherwise identically assayed,
reference sample, of preferably the same subject, which reference sample has not been
stimulated with the at least one antigen of (a),
wherein a difference in data identified in (c) is a measure for a response to the
agent. The method is herein further referred to as an assay or a method as presented
herein. An assay as presented herein preferably involves flow cytometry and preferably
is a fluorescence activated cell scanning or -sorting (FACS) assay. FACS (see e.g.
The Molecular Probes Handbook. A Guide to Fluorescent Probes and Labeling Technologies
(I. Johnson and M. Spence (eds.) 11th Edition, Life Technologies, 2010) is a method by which the individual cells of a sample are analyzed and sorted according
to their optical properties (i.e. light absorbance, light scattering, fluorescence
properties, etc.) as they pass in a narrow stream in single file through a laser beam.
The Fluorescence Activated Cell Sorter was invented in the late 1960s by Bonner, Sweet,
Hulett, Herzenberg, and others to perform flow cytometry and cell sorting of viable
cells. Becton Dickinson Immunocytometry Systems introduced the commercial machines
in the early 1970s. Fluorescence-activated cell sorting (FACS) is a specialized type
of flow cytometry. It provides a method for sorting a heterogeneous mixture of biological
cells into two or more containers, one cell at a time, based upon the specific light
scattering and fluorescent characteristics of each cell. It is a useful scientific
instrument, as it provides fast, objective and quantitative recording of fluorescent
signals from individual cells as well as physical separation of cells of particular
interest.
[0040] The cell suspension is entrained in the center of a narrow, rapidly flowing stream
of liquid. The flow is arranged so that there is a large separation between cells
relative to their diameter. A vibrating mechanism causes the stream of cells to break
into individual droplets. The system is adjusted so that there is a low probability
of more than one cell per droplet. Just before the stream breaks into droplets, the
flow passes through a fluorescence measuring station where the fluorescent character
of interest of each cell is measured. An electrical charging ring is placed just at
the point where the stream breaks into droplets. A charge is placed on the ring based
on the immediately prior fluorescence intensity measurement, and the opposite charge
is trapped on the droplet as it breaks from the stream. The charged droplets then
fall through an electrostatic deflection system that diverts droplets into containers
based upon their charge. In some systems, the charge is applied directly to the stream,
and the droplet breaking off retains charge of the same sign as the stream. The stream
is then returned to neutral after the droplet breaks off.
[0041] A wide range of fluorophores can be used as labels in flow cytometry. Fluorophores,
or simply "fluors," are typically attached to an antibody that recognizes a target
feature on or in the cell; they may also be attached to a chemical entity with affinity
for the cell membrane or another cellular structure. Each fluorophore has a characteristic
peak excitation and emission wavelength, and the emission spectra often overlap. Consequently,
the combination of labels which can be used depends on the wavelength of the lamp(s)
or laser(s) used to excite the fluorochromes and on the detectors available. Fluorescence-activated
cell sorting provides a rapid means of isolating large numbers of fluorescently tagged
cells from a heterogeneous mixture of cells.
[0042] Positive detection of a response to an agent in a flow cytometry assay as depicted
here above, preferably relies on the difference, preferably quantitative difference,
of a specific sub-population of PBMC between a sample stimulated with an antigen compared
to a reference sample not stimulated with said antigen, as depicted here above.
[0043] A person skilled in the art is well aware of stimulation assays and using FACS as
a tool for read-out. Preferably, the assays described in the examples are used in
a method as presented herein.
[0044] Preferably, the difference is an increase or maintenance in the amount of the specific
sub-population of PBMC. In case the sub-population does not change in a non-stimulated
reference sample, the difference is preferably an increase in the amount of the specific
sub-population of PBMC in the stimulated sample. In case the sub-population does not
change in the non-stimulated reference sample, the difference is preferably maintenance
(no change) or an increase in the amount of the specific sub-population of PBMC in
the stimulated sample.
[0045] Preferably, the sub-population is a population selected from the group consisting
of CD3+/CD4+ (Thelper cells), CD3+/CD4+/CD45RO- (naive Thelper cells), CD3+/CD4+/Foxp3+
cells (Foxp3+ Thelper cells), CD3+/CD4+/CD45RO+ (memory Thelper cells), CD3+/CD4+/CD45RO+/CD69+
(activated memory Thelper cells), CD3+/CD8+/CD45RO- (naive CD8+ cells), CD3+/CD8+/CD45RO+
(CD8+ memory T cells), CD3+/CD8+/CD45RO+/CD69+ (activated CD8+ memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+
cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter
memory Thelper cells).
[0046] More preferably the sub-population is an antigen specific CD45RO+ population, preferably
selected from CD3+/CD4+/CD45RO+ cells (memory Thelper cells), CD3+/CD4+/CD45RO+/CD69+
cells (activated memory Thelper cells), CD3+/CD8+/CD45RO+ cells (CD8+ memory T cells),
CD3+/CD8+/CD45RO+/CD69+ cells (activated memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+
cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter
memory Thelper cells). Further preferred sub-populations are CD3+/CD4+/Foxp3+ cells
(Foxp3+ Thelper cells), and IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells (IPNγ
and/or IL17 producing memory Thelper cells).
[0047] Preferably, in an assay as presented herein, the response is an immune response,
preferably modulation of an existing immune response, more preferably an increase
of an existing immune response, such existing immune response preferably being as
described previously herein.
[0048] Preferably, in a method as presented herein, the agent is a food product, preferably
a probiotic, more preferably the agent or part thereof comprises a membrane of a probiotic.
Preferably, in a method as presented herein, the sample comprises a bodily fluid;
preferably the sample is a blood sample.
[0049] A blood sample in the context of the present disclosure preferably is a sample of
whole blood or of a sub-population of cells of whole blood. Sub-populations of cells
of whole blood include but are not limited to PBMC or a sub-population thereof such
as lymphocytes, monocytes, and macrophages. PBMC are a critical component of the immune
system to fight infection and adapt to intruders.
[0050] Preferably, in a method as presented herein, the at least one antigen in (a) is selected
from the group consisting of a general T cell stimulator such as a superantigen, a
Protein Kinase A (PKA) stimulator such as a lectin, a recall antigen, i.e. an antigen
that the individual has encountered previously, preferably selected from the group
consisting of tetanus toxin, Hepatitis B antigen and Influenza, or the agent or a
part thereof.
[0051] Preferably, in a method as presented herein, the at least one antigen of (a) comprises
at least:
- a. a recall antigen such as tetanus toxin, a Hepatitis B antigen or an Influenza antigen,
and
- b. the agent or a part thereof.
[0052] Preferably, in a method presented herein, the sub-population is a population selected
from the group consisting of CD3+/CD4+ (Thelper cells), CD3+/CD4+/CD45RO- (naive Thelper
cells), CD3+/CD4+/Foxp3+ cells (Foxp3+ Thelper cells), CD3+/CD4+/CD45RO+ (memory Thelper
cells), CD3+/CD4+/CD45RO+/CD69+ (activated memory Thelper cells), CD3+/CD8+/CD45RO-
(naive CD8+ cells), CD3+/CD8+/CD45RO+ (CD8+ memory T cells), CD3+/CD8+/CD45RO+/CD69+
(activated CD8+ memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+ cells (central memory
Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter memory Thelper cells).
[0053] More preferably the sub-population is an antigen specific CD45RO+ population, preferably
selected from CD3+/CD4+/CD45RO+ cells (memory Thelper cells), CD3+/CD4+/CD45RO+/CD69+
cells (activated memory Thelper cells), CD3+/CD8+/CD45RO+ cells (CD8+ memory T cells),
CD3+/CD8+/CD45RO+/CD69+ cells (activated memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+
cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter
memory Thelper cells). Further preferred sub-populations are CD3+/CD4+/Foxp3+ cells
(Foxp3+ Thelper cells), and IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells (IFNγ
and/or IL17 producing memory Thelper cells).
[0054] Preferably, in a method as presented herein, the identification of the sub-population
of PBMC comprises flow cytometry analysis as depicted here above; preferably the identification
of the sub-population of PBMC comprises quantification. Quantification in an assay
as presented herein, preferably relates to determining the percentage of one or more
sub-populations of PBMC, preferably of at least one sub-population selected form the
group consisting of CD3+/CD4+ (Thelper cells), CD3+/CD4+/CD45RO- (naive Thelper cells),
CD3+/CD4+/Foxp3+ cells (Foxp3+ Thelper cells), CD3+/CD4+/CD45RO+ (memory Thelper cells),
CD3+/CD4+/CD45RO+/CD69+ (activated memory Thelper cells), CD3+/CD8+/CD45RO- (naive
CD8+ cells), CD3+/CD8+/CD45RO+ (CD8+ memory T cells), CD3+/CD8+/CD45RO+/CD69+ (activated
CD8+ memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+ cells (central memory Thelper
cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter memory Thelper cells).
[0055] More preferably the sub-population is an antigen specific CD45RO+ population, preferably
selected from CD3+/CD4+/CD45RO+ cells (memory Thelper cells), CD3+/CD4+/CD45RO+/CD69+
cells (activated memory Thelper cells), CD3+/CD8+/CD45RO+ cells (CD8+ memory T cells),
CD3+/CD8+/CD45RO+/CD69+ cells (activated memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+
cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter
memory Thelper cells). Further preferred sub-populations are CD3+/CD4+/Foxp3+ cells
(Foxp3+ Thelper cells), and IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells (IFNγ
and/or IL17 producing memory Thelper cells).
[0056] Further provided is the use of a sub-population of PBMC as a biomarker for efficacy
testing of immune modulating agents. The term biomarker (or biological marker) refers
to a distinct biochemical, genetic, or molecular characteristic or substance that
is an indicator of a particular biological condition or process. Within the context
of the present disclosure a sub-population of PBMC as defined herein is used as biomarker.
[0057] Preferably, the immune modulating agent is a food product, preferably a probiotic
such as described previously herein. Preferably, the sub-population of PBMC one such
as previously described herein; preferably, the sub-population is a population selected
from the group consisting of CD3+/CD4+ (Thelper cells), CD3+/CD4+/CD45RO- (naive Thelper
cells), CD3+/CD4+/Foxp3+ cells (Foxp3+ Thelper cells), CD3+/CD4+/CD45RO+ (memory Thelper
cells), CD3+/CD4+/CD45RO+/CD69+ (activated memory Thelper cells), CD3+/CD8+/CD45RO-
(naive CD8+ cells), CD3+/CD8+/CD45RO+ (CD8+ memory T cells), CD3+/CD8+/CD45RO+/CD69+
(activated CD8+ memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+ cells (central memory
Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter memory Thelper cells).
[0058] More preferably the sub-population is an antigen specific CD45RO+ population, preferably
selected from CD3+/CD4+/CD45RO+ cells (memory Thelper cells), CD3+/CD4+/CD45RO+/CD69+
cells (activated memory Thelper cells), CD3+/CD8+/CD45RO+ cells (CD8+ memory T cells),
CD3+/CD8+/CD45RO+/CD69+ cells (activated memory T cells), CD3+/CD4+/CD45RO+/CCR7+/CD62L+
cells (central memory Thelper cells), CD3+/CD4+/CD45RO+/CCR7-/CD62L- cells (effecter
memory Thelper cells). Further preferred sub-populations are CD3+/CD4+/Foxp3+ cells
(Foxp3+ Thelper cells), and IFNγ and/or IL17 producing CD3+/CD4+/CD45RO+ cells (IFNγ
and/or IL17 producing memory Thelper cells).
Definitions
[0059] The genome of
Lactobacillus plantarum TIFN 101 is the genome of the strain deposited under number CBS 138100 at the Centraalbureau
voor Schimmelcultures, Uppsalalaan 8, 3584 CT The Netherlands. SEQ ID NO: 175 represents
a scaffold of 174 contigs of TIFN 101 and is for the context of the present invention
construed as the preferred genome sequence of TIFN 101.
[0060] "Sequence identity" or "identity" in the context of amino acid- or nucleic acid-sequence
is herein defined as a relationship between two or more amino acid (peptide, polypeptide,
or protein) sequences or two or more nucleic acid (nucleotide, polynucleotide) sequences,
as determined by comparing the sequences. In the art, "identity" also means the degree
of sequence relatedness between amino acid or nucleotide sequences, as the case may
be, as determined by the match between strings of such sequences. At least 50% sequence
identity is to be construed as preferably at least 50%, more preferably 55%, 60%,
65%, 70%, 75%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%,
94% 95%, 96%, 97%, 98%, 99% and most preferably at least 100% sequence identity with
the genome of
Lactobacillus plantarum TIFN 101, or with a polynucleotide sequence selected from the group consisting of
SEQ ID NO: 1 - SEQ ID NO: 174 or with a polynucleotide encoding a polypeptide with
a sequence selected from the group consisting of SEQ ID NO: 245 - SEQ ID NO: 327.
Sequence identity with a particular sequence preferably means sequence identity over
the entire length of said particular polypeptide or polynucleotide sequence. The sequence
information as provided herein should not be so narrowly construed as to require inclusion
of erroneously identified bases. The skilled person is capable of identifying such
erroneously identified bases and knows how to correct for such errors.
[0061] "Similarity" between two amino acid sequences is determined by comparing the amino
acid sequence and its conserved amino acid substitutes of one peptide or polypeptide
to the sequence of a second peptide or polypeptide. Identity or similarity is calculated
over the whole SEQ ID NO as identified herein. "Identity" and "similarity" can be
readily calculated by known methods, including but not limited to those described
in
Computational Molecular Biology, Lesk, A. M., ed., Oxford University Press, New York,
1988;
Biocomputing: Informatics and Genome Projects, Smith, D. W., ed., Academic Press,
New York, 1993;
Computer Analysis of Sequence Data, Part I, Griffin, A. M., and Griffin, H. G., eds.,
Humana Press, New Jersey, 1994;
Sequence Analysis in Molecular Biology, von Heine, G., Academic Press, 1987; and
Sequence Analysis Primer, Gribskov, M. and Devereux, J., eds., M Stockton Press, New
York, 1991; and
Carillo, H., and Lipman, D., SIAM J. Applied Math., 48:1073 (1988). Preferred methods to determine identity are designed to give the largest match
between the sequences tested. Methods to determine identity and similarity are codified
in publicly available computer programs. Preferred computer program methods to determine
identity and similarity between two sequences include e.g. the GCG program package
(
Devereux, J., et al., Nucleic Acids Research 12 (1): 387 (1984)), BestFit, BLASTP, BLASTN, and FASTA (
Altschul, S. F. et al., J. Mol. Biol. 215:403-410 (1990). The BLAST X program is publicly available from NCBI and other sources (
BLAST Manual, Altschul, S., et al., NCBI NLM NIH Bethesda, MD 20894;
Altschul, S., et al., J. Mol. Biol. 215:403-410 (1990). The well-known Smith Waterman algorithm may also be used to determine identity.
[0062] Preferred parameters for polypeptide sequence comparison include the following: Algorithm:
Needleman and Wunsch, J. Mol. Biol. 48:443-453 (1970); Comparison matrix: BLOSSUM62 from
Hentikoff and Hentikoff, Proc. Natl. Acad. Sci. USA. 89:10915-10919 (1992); Gap Penalty: 12; and Gap Length Penalty: 4. A program useful with these parameters
is publicly available as the "Ogap" program from Genetics Computer Group, located
in Madison, WI. The aforementioned parameters are the default parameters for amino
acid comparisons (along with no penalty for end gaps). Preferred parameters for nucleic
acid comparison include the following: Algorithm:
Needleman and Wunsch, J. Mol. Biol. 48:443-453 (1970); Comparison matrix: matches=+10, mismatch=0; Gap Penalty: 50; Gap Length Penalty:
3. Available as the Gap program from Genetics Computer Group, located in Madison,
Wis. Given above are the default parameters for nucleic acid comparisons.
[0063] Optionally, in determining the degree of amino acid similarity, the skilled person
may also take into account so-called "conservative" amino acid substitutions, as will
be clear to the skilled person. Conservative amino acid substitutions refer to the
interchangeability of residues having similar side chains. For example, a group of
amino acids having aliphatic side chains is glycine, alanine, valine, leucine, and
isoleucine; a group of amino acids having aliphatic-hydroxyl side chains is serine
and threonine; a group of amino acids having amide-containing side chains is asparagine
and glutamine; a group of amino acids having aromatic side chains is phenylalanine,
tyrosine, and tryptophan; a group of amino acids having basic side chains is lysine,
arginine, and histidine; and a group of amino acids having sulphur-containing side
chains is cysteine and methionine. Preferred conservative amino acids substitution
groups are: valine-leucine-isoleucine, phenylalanine-tyrosine, lysine-arginine, alanine-valine,
and asparagine-glutamine. Substitutional variants of the amino acid sequence disclosed
herein are those in which at least one residue in the disclosed sequences has been
removed and a different residue inserted in its place. Preferably, the amino acid
change is conservative. Preferred conservative substitutions for each of the naturally
occurring amino acids are as follows: Ala to ser; Arg to lys; Asn to gln or his; Asp
to glu; Cys to ser or ala; Gln to asn; Glu to asp; Gly to pro; His to asn or gln;
Ile to leu or val; Leu to ile or val; Lys to arg; gln or glu; Met to leu or ile; Phe
to met, leu or tyr; Ser to thr; Thr to ser; Trp to tyr; Tyr to trp or phe; and, Val
to ile or leu.
[0064] A polynucleotide is represented by a nucleotide sequence. A polypeptide is represented
by an amino acid sequence.
[0065] In this document and in its claims, the verb "to comprise" and its conjugations is
used in its non-limiting sense to mean that items following the word are included,
but items not specifically mentioned are not excluded. In addition, reference to an
element by the indefinite article "a" or "an" does not exclude the possibility that
more than one of the element is present, unless the context clearly requires that
there be one and only one of the elements. The indefinite article "a" or "an" thus
usually means "at least one".
[0066] The word "about" or "approximately" when used in association with a numerical value
(e.g. about 10) preferably means that the value may be the given value (of 10) more
or less 0.1% of the value.
Figure legends
[0067]
Figure 1. Effects of three L. plantarum strains on frequency of different CD4+ (a-f) and CD8+ (g-j) T-cell population in
the systemic circulation (n=9). Statistical significance was calculated using the
Students t- test.
Figure 2. Effects of three L. plantarum strains on frequency of IL21 (a), IL17 (b), IL4 (c), and IFNγ-producing (d) superantigen
(SEB) stimulated memory-Th cells (n=9). Statistical significance was calculated using
the Students t- test.
Figure 3. Effects of three L. plantarum strains on frequency of IL21 (a), IL17 (b), IL4 (c), and IFNγ-producing (d) Staphylococcus aureus enterotoxin B superantigen (SEB) stimulated memory-CD45RO+ Th cells (n=9). Statistical
significance was calculated using the Students t- test.
Figure 4. Effects of three L. plantarum strains on frequency of IL21 (a), IL17(b), IL4(c), and IFNγ-producing (d) tetanus
toxoid (TT) stimulated memory- CD45RO+ Th cells (n=9). Statistical significance was
calculated using the Students t- test.
Figure 5. The Flowchart of microarray analysis (a) and the number of unique genes
that are regulated in the intestinal biopsis of the human consumers of three different
L. plantarum strains (L. plantarum WCFS1 (WCFS1), L. plantarum CIP104448 (CIP48), L. plantarum TIFN 101. Intensity > 20 on at least 5 arrays, interquartile range > 0.2, at least
7 probes per gene. (b) Venn diagram chart of the number of upregulated and (c) downregulated
genes in the intestinal biopsies after consumption of l. plantarum and indomethacin.
Examples
[0068] The present invention is further described by the following examples which should
not be construed as limiting the scope of the invention.
[0069] Unless stated otherwise, the practice of the invention will employ standard conventional
methods of molecular biology, virology, microbiology or biochemistry. Such techniques
are described in
Sambrook et al. (1989) Molecular Cloning, A Laboratory Manual (2nd edition), Cold
Spring Harbor Laboratory, Cold Spring Harbor Laboratory Press; in
Sambrook and Russell (2001) Molecular Cloning: A Laboratory Manual, Third Edition,
Cold Spring Harbor Laboratory Press, NY; in
Volumes 1 and 2 of Ausubel et al. (1994) Current Protocols in Molecular Biology, Current
Protocols, USA; and in
Volumes I and II of Brown (1998) Molecular Biology LabFax, Second Edition, Academic
Press (UK);
Oligonucleotide Synthesis (N. Gait editor); Nucleic Acid Hybridization (Hames and
Higgins, eds.).
[0070] Example 1. Differential human mucosal transcriptomic and immune responses to three probiotic
strains; insight in how probiotics contribute to immunity in healthy individuals.
Materials and Methods
Bacterial Strains and Growth Conditions
[0071] Lactobacillus plantarum WCFS1 (Kleerebezem et al., 2003),
Lactobacillus plantarum CIP104448 (CIP48), and
Lactobacillus plantarum TIFN 101 were cultured at 37 °C in Man, Rogosa and Sharpe (MRS) medium (Merck). To
obtain stationary-phase cultures, bacteria were cultured overnight. Maltodextrin and
glucose were added to a final concentration of 20% and 2% (wt/vol), respectively,
to obtain bacterial preparations (WCFS1, 2.6 x 10
9 CFU; CIP48, 2.4 x 10
9 CFU; TIFN 101, 5.6 x 10
9 CFU); placebo controls only contained the two sugars. Bacteria and placebo materials
were prepared such that they contained similar final sugar concentrations. Detailed
protocols for culturing, harvesting, freeze-drying, storing, and viable count determining
of
Lactobacillus species can be found in Smelt et al. 2012.
Volunteers and interventions
[0072] This study was approved by the University Hospital Maastricht Ethical Committee and
was conducted in accordance with the principles of the Declaration of Helsinki. All
subjects gave their written informed consent before their inclusion in the study.
Ten healthy volunteers, 7 female and 3 male (26.3±10.1 years, BMI of 21.8±2.40 kg/m
2), without a history of gastrointestinal symptoms and free of any form of medication,
were tested on four separate occasions (three bacterial interventions and one placebo
control, randomly chosen) in a randomized placebo-controlled cross-over study. The
volunteers consumed habitual diet during the study period and were asked to fill in
a gastrointestinal symptoms diary. Three days before the intervention a blood sample
was taken to obtain baseline values. The night before the start of the supplements
intake period the volunteers ingested 75 mg of indomethacin. At the starting day the
volunteers ingested another dosage of 50 mg indomethacin conform previously established
protocol to establish mild gastrointestinal stress (Troost et al., 2003). Subsequently,
the volunteers consumed the probiotic or placebo supplements for a period of 7 days
during lunch and during dinner;
L. plantarum WCFS1 (2.6
10 colony forming units (cfu) per shot),
L. plantarum CIP104448 (2.4
10 cfu/shot),
L. plantarum TIFN 101 (5.9
10 cfu/shot) or placebo. Neither the volunteers nor the researchers knew which subject
received the
L. plantarum strains or the placebo (double-blinded study); the vials containing bacteria or placebo
control were non-transparent. On the 7
th day, tissue samples were obtained from the horizontal part of the duodenum by standard
flexible gastroduodenoscopy at approximately 15 cm distal to the pylorus. The duodenal
mucosa was chosen as this is the first intestinal segment coming in contact with the
bacteria, minimizing the adaptive changes microbes might go through during passage
of the intestinal tract. Also, the duodenum is readily accessible for mucosal tissue
sampling. Finally, the duodenum contains the lowest endogenous microbiota colonization
level, ensuring that the measured responses are as specific as can be achieved. The
interventions were performed with an interval of 4 weeks to allow a wash-out period
and to allow healing of the biopsy-sampling region.
Cell staining
[0073] The various dilutions of the antibodies and other reagents used for cell staining
are listed in Table 1.
[0074] Blood was collected in EDTA containing tubes and processed for FACS analysis. The
following antibodies were used for staining of the T cell sub-populations: Pacific
Blue-conjugated anti-CD3 (clone UCHT1; BD Pharmingen), PerCP conjugated anti-CD8 (clone
SKI, Biolegend), APC-Cy7-conjugated anti-CD69 (clone FN50, BD Pharmingen), APC-conjugated
anti-FoxP3 (clone 206D, eBioscience), biotin-conjugated anti-CD45RO (UCHL1, Biolegend)
with Pacific orange conjugated streptavidin (Invitrogen). Isotype controls were purchased
from the same company as the antibodies and used in the same dilution as the antibody.
[0075] For intracellular cytokine staining of T cells we used: PE-Cy7 conjugated anti-IL4
(MP4-25D2, Biolegend), Alexa488-conjugated anti-IL-17A (clone eBio64DEC17; eBioscience),
PE-conjugated anti-IL-21 (clone eBio3A3-N2; eBioscience), Alexa700-conjugated anti-IFNγ
(clone B27; BD Pharmingen),
[0076] For staining of the NK cell populations we used: APC-conjugated anti-CD56 (clone
MEM-188, Ebioscience), EFluor450-conjugated anti-CD16 (clone CB16, eBioscience), PE-conjugated
anti-CD335 (clone 9E2, Biolegend), PE-Cy7-conjugated anti-CD161 (clone HP-3G10, eBioscience)
T-cell prolarization was studied after three types of stimulations of the T-cells.
It was done by (i) aspecific stimulation with PMA/Ca
2+ or superantigen (SEB) to study whether the total responsiveness was influenced by
probiotic treatment, by (ii) stimulation with cell extracts of the specific
L. plantarum strains in order to investigate whether specific immune responses against the probiotic
was stimulated, and (iii) by stimulating with an antigen to which all volunteers were
vaccinated, tetanus toxoid (TT), to study possible stimulation of specific memory
responses.
[0077] After blood sampling, 200 µl of blood was diluted with 200 µl of RPMI1640 supplemented
with 10 % fetal calf serum (FCS) and incubated with either PMA (Phorbol myristate
acetage; 80 nM Sigma-Aldrich, Steinheim, Germany) and Ca2+ (4 µM) (4 hr),
Staphylococcus aureus enterotoxin B SEB (5 µg/mL Sigma, Deisenhofen, Germany) (24 hr), TT (tetanus toxoid;1.5
Lf/mL) (24 hr) or bacterial lysates (30 µg/mL) (24 hr). Stimulation with bacterial
lysates was according to the administered strain and performed one week after treatment.
After the treatment week with
L. plantarum WCFS1, samples were stimulated with cell extracts of
L. plantarum WCFS1; after the treatment week with
L. plantarum CIP104448, samples were stimulated with cell extracts
of L. plantarum CIP104448; after the treatment week with
L. plantarum TIFN 101, samples were stimulated with cell extracts of
L. plantarum TIFN 101. These cell extracts were made by repeated freeze-thawing of the probiotics.
[0078] After stimulation, red blood cells were lysed with ammonium chloride. After washing
(PBS with 2 % FCS), cells were incubated with different antibody cocktails.
[0079] Staining for T cells and T cell subsets: Cells were incubated with an antibody cocktail
consisting of anti-CD3, anti-CD8 and anti-CD45RO for 30 minutes in the dark on ice.
After washing with washing buffer, cells were incubated with streptavidine Pacific
Orange (1:100 Invitrogen) for 15 minutes on ice. After washing and spinning down,
pelleted cells were resuspended in Fixation/Permeabilization solution (eBioscience,
0.1% saponin and 0.009% sodium azide) for 45 minutes on ice. After washing in Perm
solution (eBioscience), cells were incubated in mouse serum for 15 minutes to prevent
non-specific binding, followed by incubation with the cytokine antibody mix (anti-IL-4,
anti-IFNy, anti-IL-17 and anti-IL21) or an isotype cytokine mix for 30 minutes on
ice. After washing with Permeabilization solution (3 times) cells were resuspended
in wash-buffer and measured by flow cytometry within 24 hrs.
[0080] Staining for NK cells: Cells were incubated with an antibody cocktail consisting
of anti-CD3, anti-CD16, anti-CD56, anti-CD335 and anti-CD161 (NK cell staining), or
with isotype control cocktail for NK cells consisting of anti-CD3, anti-CD16, anti-CD56
and isotype controls for anti-CD335 and CD161 for 30 minutes in the dark on ice. After
washing with washing buffer, cells were fixed in FACS lysing solution (BD Biosciences,
phosphate buffered saline (PBS) containing 2% heat-inactivated fetal calf serum (FCS))
for 30 minutes on ice. After washing, cells were suspended in washing buffer and measured
by flow cytometry on a Becton and Dickinson LSRII within 24 hrs; at least 500.000
events were recorded per sample.
Table 1: Antibody dilutions
| # |
Reactivity |
Isotype |
Label |
Dilution |
Company |
| 1A |
CD3 |
mIgG1 (UCTH1) |
Pac Blue |
1:25 |
BD 558117 |
| 2 |
CD8 |
mIgG1 (SK1) |
PerCP |
1:25 |
BD 345774 |
| 4 |
IL17A |
mIgG1 (eBio64DEC17) |
Alexa488 |
1:25 |
eBio 53-7179 |
| 5 |
IL21 |
mIgG1 (eBio3A3-N2) |
PE |
1:25 |
eBio 12-7219 |
| 6 |
IFNg |
mIgG1 (B27) |
Alexa700 |
1:100 |
BD 557995 |
| 7 |
CD69 |
mIgG1 (FN50) |
APC-Cy7 |
1:25 |
BD 557756 |
| 8 |
FoxP3 |
mIgG1 (206D) |
APC |
1:25 |
eBio 9017-4776-220 |
| 9 |
CD45RO |
mIgG2a (UCHL1) |
Biotin |
1:25 |
BioLegend 304220 |
| 10 |
Streptavidin |
|
Pac Orange |
1:100 |
Invitrogen |
| 11 |
CD3 |
mIgG1 (UCHT1) |
PerCP |
1:30 |
BioLegend 300428 |
| 12 |
CD16 |
mIgG1 (CB16) |
eFluor450 |
1:10 |
eBio 48-0168-42 |
| 13 |
CD56 |
mIgG2a (MEM-188) |
APC |
1:25 |
eBio 17-0569-42 |
| 14 |
CD335 |
mIgG1 (9E2) |
PE |
1:7.5 |
BioLegend 331908 |
| 15 |
CD161 |
mIgG1 (HP-3G10) |
PE-Cy7 |
1:20 |
eBio 25-1619-42 |
| 17 |
- |
Mouse IgG1 |
PE |
1:62.5 |
BioLegend 400112 |
| 18 |
- |
Mouse IgG1 |
PE-Cy7 |
1:20 |
eBio 25-4714 |
| 20 |
IL4 |
rIgG1 (MP4-25D2) |
PE-Cy7 |
1:25 |
BioLegend 500824 |
RNA isolation and microarray
[0081] Total RNA was isolated from the duodenal biopsies by using Trizol reagent (1 ml)
(Invitrogen, Breda, NL). Thereafter RNA was purified using the Qiagen RNeasy Micro
kit (Qiagen, Venlo, NL). RNA was quantified on a NanoDrop ND-1000 spectrophotometer
(Isogen Life Science, De Meer, The Netherlands) RNA quality was checked using an Agilent
2100 bioanalyzer (Agilent Technologies, Amsterdam, NL). RNA was judged suitable for
array hybridization only if samples exhibited intact bands corresponding to 18S and
28S ribosomal subunits and displayed no chromosomal peaks or RNA degradation products.
[0082] Total RNA (100 ng) was used for whole transcript cDNA synthesis by using the Ambion
WT expression kit (Life Technologies, Bleiswijk, The Netherlands) and subsequently
labelled by using the Affymetrix GeneChip WT Terminal Labelling Kit (Affymetrix, Santa
Clara CA). Samples were hybridized to human whole genome Affymetrix GeneChip Human
Gene 1.1 ST arrays, washed, stained, and scanned on an Affymetrix GeneTitan instrument.
Details on array handling can be found in the Affymetrix GeneTitan Instrument User
Guide for Expression Array Plates (P/N 702933 Rev.2).
Microarray data analysis
[0083] Microarray analysis was performed by applying MADMAX for statistical analysis (
Lin et al 2011, J Integr Bioinform, PMID 21778530). Quality control was performed. All arrays met the criteria. The probes on the Human
Gene 1.1 ST arrays were redefined according to
Dai et al (2005, Nucleic Acids Res PMID 16284200) based on the NCBI Entrez database (CDF version 15.1). In this way the Human Gene
1.1 ST array targets 19,682 unique genes. Normalized expression values were obtained
from the raw intensity values by using the robust multiarray analysis preprocessing
algorithm available in the library AffyPLM using default setting (
Irizarry et al, Biostatistics, 2003, PMID 12925520). Microarray data were filtered, and probe sets with at least 5 probes and expression
values higher than 20 on at least 5 arrays, and a interquartile range >0.2 (log2 scale)
across all samples were and selected for further statistical analysis. In addition,
an Inter Quartile Range (IQR) cut-off of 0.2 was used to filter out genes that showed
no variation between the conditions. Differentially expressed genes were identified
by using linear models, applying moderated t-statistics that implemented empirical
Bayes regularization of standard errors in the library limma (Smyth et al., 2004)).
To adjust for both the degree of independence of variances relative to the degree
of identity and relation between variance and signal intensity, the moderated t-statistic
was extended by a Bayesian hierarchical model to define an intensity-based moderated
t-statistic (
Sartor et al, 2006, BMC Bioinformatics PMID 17177995). Genes were defined as significantly changed when the P value was <0.05 for pairwise
comparisons.
Pathway analysis
[0084] Geneset enrichment analysis (GSEA; at world wide web: broad.mit.edu/gsea/) was performed
using MADMAX and genesets with a false discovery rate (FDR)<0.2 were considered significantly
enriched. GSEA takes into account the broader context in which gene products function,
namely in physically interacting networks such as biochemical, metabolic, or signal
transduction routes, and has the advantage that it is unbiased, because no gene selection
step is used (Subramanian et al., 2005. Possible transcription factors playing a role
in the activation and inhibition of genes were identified using Upstream Regulator
Analysis in Ingenuity Pathway Analysis (IPA; Ingenuity Systems, Redwood City, CA).
Genome sequencing and annotation
[0085] The
L. plantarum strain CIP104448 was obtained from the NIZO culture collection (Meijerink et al.,
2010). For DNA preparation, 2 ml of overnight culture was pelleted, washed and resuspended
in TES buffer (N-[tris(hydroxymethyl)methyl]-2-aminoethanesulfonicacid). Cells were
lysed with lysozyme (360 mg/ml) and mutanolysin (140 U /ml) by incubation for 2 h
at 37°C. Subsequently 300 µl water was added and 80 µl of 20% SDS solution. The DNA
extraction was done using phenol/chloroform (3×). The DNA was precipitated with isopropanol
and washed with 70% ethanol. Samples were treated with 100 µg/ml RNAse (Sigma) during
1 hour at 37°C. DNA paired-end libraries with barcoding were made and sequenced using
Illumina technology (Baseclear Leiden, NL). The contig sequences were submitted to
the RAST automatic annotation server, which provided ORF calling and automatic annotation.
The annotated contigs of CIP48 and TIFN 101 were ordered by comparing them to the
circular template genome of
L. plantarum WCFS1, and comparing them to each other. Contigs/genes which did not match to the
WCFS1 genome were annotated in more detail using BLASTP (http://blast.ncbi.nlm.nih.gov/)
and InterProscan (http://www.ebi.ac.uk/interpro/). Ortholog groups (OGs) in the 3
genomes were determined using OrthoMCL
(www.orthomcl.orgl)..
Statistics
[0086] Flow cytometry data results are expressed as the mean ± standard error of the mean
(SEM). Normal distribution of the data sets was confirmed by the Kolmogorov-Smirnov
test. The two-sided Students t-test was used to determine changes in immune cell populations
after probiotic treatment. Gene expression data are depicted as the medium (range).
The two-sided Mann Whitney U-test was used to determine changes in expression profiles
after probiotic treatment
in vivo. P-values < 0.05 (*) were considered statistically significant.
Results
Human trial
[0087] None of the volunteers experienced any discomfort during or after the 7 days consumption
period. Before the start of the trial (day 0), and at day 7 blood samples were taken
to study the effect of probiotic consumption on T-cell polarization. Also at day 7
biopsies were taken by standard flexible gastroduodenoscopy, and total RNA was isolated
and hybridized to whole-genome expression microarrays. Quality control of the hybridizations
and primary data analysis were performed according to strict criteria to ensure that
the array data were of the highest possible quality.
Differential peripheral responses induced by L. plantarum
[0088] L. plantarum WCFS1,
L. plantarum CIP104448, and
L. plantarum TIFN 101 were selected from a series of 42 individual
L. plantarum strains which were assayed for the levels of IL-10 and IL12 they induced from dendritic
cells (Meijerink et al., 2010).
L. plantarum WCFS1 is characterized by a relative low IL10/IL12 ratio and classified as proinflammatory,
L. plantarum CIP104448, does not change the IL10/IL12 ratio when compared to medium control and
is therefore classified as neutral and
L. plantarum TIFN 101 induces a relative high IL10/IL12 ratio and is therefore classified as anti-inflammatory
(Meijerink et al., 2010).
Cell frequencies after 6 days of treatment with L. plantarum
[0089] We did not observe differences in the frequencies of the total percentage of CD3+
cells, the CD3+/CD4+ cells (naive or memory), or the activated memory CD3-/CD4+ cells
after treatment with either
L. plantarum strain. However, the percentage of CD4+/Foxp3 positive cells was significantly decreased
following placebo and CIP 48 treatment, but not after WCFS1 and TIFN 101 treatment
(Figure 1a-f). Moreover, although we did not find an effect of treatment on CD3+/CD8+
naive and memory cells, activated memory cells were statistically significantly decreased
by CIP48 treatment only (P < 0.01) (Figure 1g-j).
[0090] Treatment did not affect total NK cell numbers or NKT numbers. There was also no
change in the percentages of the NK cell subtypes (i.e. CD56hi and CD56dim), while
the expression of CD161 (KLRB1), mediating cytotoxicity (Jacobs et al., 2001; Tarazona
et al., 2002), was also not affected by the
L. plantarum treatments.
[0091] T-cell polarization was studied after three types of stimulations of the T-cells.
It was done by (i) non-specific stimulation with PMA/Ca
2+ or superantigen (SEB) to study whether the total responsiveness was influenced by
L. plantarum treatment, by (ii) stimulation with cell extracts of the specific
L. plantarum strains in order to investigate whether specific immune responses against the
L. plantarum was stimulated, and (iii) by stimulation with a previously administered vaccine antigen
(TT) to study possible stimulation of specific memory responses.
[0092] After non-specific stimulation with PMA /Ca-ionophore or SEB, we studied the percentage
of IFNγ, IL-4, Il-17 or IL-21 positive Th cells and memory Th cells. Treatment with
placebo or the administered
L. plantarum strains did not influence cytokine production of the total population of Th cells
or of the Th memory cells after non-specific stimulation with PMA/Ca-ionophore (results
not shown). Although after SEB stimulation no differences were found in cytokine production
of the total Th cell population after the three
L. plantarum treatments (results not shown), we did observe differences in cytokine production
of the Th memory cells after
L. plantarum treatment. After stimulation with SEB (Figure 2a-d), we observed a decreased percentage
of IL-17 producing activated memory Th cells following treatment with CIP48 and an
increased percentage of IL-17 producing activated memory Th cells after treatment
with TIFN 101 (Figure 2b). Moreover the percentage of IFNγ producing activated memory
Th cells was also increased after TIFN 101 treatment (Figure 2d).
[0093] Treatment with
L. plantarum strains also affected the cytokine production following a more specific stimulation
by TT (Figure 3a-d). We studied cytokine production of memory Th cells in order to
study the effect
of L. plantarum treatment on memory T cells. After TIFN 101 treatment, the percentage IL-17 and the
percentage IFNγ producing activated memory Th cells were significantly increased (Figures
3b and 3d, respectively, while no effects of the other
L. plantarum on cytokine production of memory Th after TT stimulation were observed.
[0094] Finally, we stimulated blood samples of the individuals with cell extracts of the
L. plantarum strain that they had consumed in the study (Figure 4a-d). We observed that subjects
who were treated with WCFS1, showed an increased IL-17 response after stimulation
with WCFS1 cell extracts (Figure 4b). Other cytokines were not affected by this treatment.
There were no differences in cytokine production in subjects when treated with CIP48,
when their blood was stimulated with CIP48 cell extract. When subjects were treated
with TIFN 101, their activated memory cells showed an increased IL-17 and IFNγ production
following stimulation with TIFN 101 cell extract (Figures 4 b and d, respectively).
Differential transcriptional response in duodenal mucosa upon exposure to the three
L. plantarum strains
[0095] Although, we compared strains and not different species we found very different numbers
of genes that were up- or downregulated in the stressed intestine of the subjects
exposed to the three
L. plantarum strains. After treatment with the three strains, 315 genes were differentially regulated
with
L. plantarum WCFS1, 390 with CIP48 and as many as 779 with TIFN 101 (Figure 5a). Of these genes
WCFS1 shared only 35 upregulated genes with CIP48 and 9 with TIFN 101 (Figure 5b).
An additional 19 genes were downregulated when CIP48 was compared with WCFS1 and another
5 with TIFN 101 (Figure 5c). Shared genes were mainly involved in general cellular
functions and metabolism. As expected, in an indomethacin-stressed intestine also
in placebo treated controls, expression of many genes associated with cellular repair
were upregulated. To gain more insight into the changes induced by the
L. plantarum treatment, genes were subsequently ranked according to mean fold-change in expression.
Listed are the 10 highest induced and 10 lowest induced genes in Tables 2-3. WCFS1
and CIP48 shared the downregulation of 6 small nucleolar RNAs (snoRNAs), i.e. snoRNA,
(H)C/D(ACA) box 6, 14b, 53, 57, 60, 388.
[0096] TIFN 101 produced a completely different profile (Table 4). Of the most highly induced
genes in TIFN 101, (the most immunological active
L. plantarum) 8 of the 10 are related to immunity, these are immunoglobulin lambda variable 6-57,
putative V-set and immunoglobulin domain-containing protein 6-like, immunoglobulin
lambda variable 7-46, interferon regulatory factor 4, GDNF family, CD27, CD79a, and
plasminogen activator.
[0097] Based on the immune data we expected to find differential changes by specific transcription
factors. To identify these transcription factors and to identify pathways regulated
by the different strains, we performed Ingenuity Pathway Analysis (IPA). IPA uses
information from literature combined with gene expression changes to predict a role
of transcription factors in the dataset. TIFN 101 induced more changed than CIP48
and WCSF1 in the NSAID-stressed intestine. The most significant set of target genes
in the TIFN 101 group were immunology related genes. TIFN 101 upregulated MHC-II α
while with CIP48 and WCFS1 we found a downregulation of MHC-II β. This might explain
the enhanced responses to antigens such as TT in the TIFN 101 treated group. Another
pathway that might contribute to the enhanced responses in TIFN 101 is the upregulation
of genes involved in leucocyte extravasation. An interesting observation is that TIFN
101 enhances RAPL which is a GTPase involved in regulating integrin affinity and enhancing
the adhesion of leucocytes. Concomitantly an upregulation of essential adhesion molecules
such as ICAM-1 and Cadherin 5 (CDH-5) was upregulated illustrating the upregulation
of immune cell migration pathways by TIFN 101. Also with CIP48 and WCFS1 some regulation
of leukocyte extravasation was observed but this was much less pronounced than for
the TIFN 101 group.
Differential gene expression profiles between the three L. plantarum strains
[0098] Due to the differential effects of the three
L. plantarum strains,
L. plantarum CIP 104448, and
L. plantarum TIFN 101 were sequenced, annotated and compared with the genome (chromosome and plasmids)
of
L. plantarum WCFS1 (Siezen et al., 2012). A total of 3010 ortholog groups (OGs) were assigned
to the chromosome based on this ordering of contigs to the template WCFS1 genome.
The three genomes shared 2455 of the 3010 chromosomal OGs (=81.5%), which is defined
as the core genome for this study. Unique genes in TIFN 101 are listed in Table 5.
When the contigs and OGs/genes are included that do not match to the WCFS1 chromosome
much higher numbers of unique genes are found for the CIP48 and TIFN 101 genomes.
Many of the unique genes in TIFN 101 are on plasmids (see Table 5). The analysis e.g.
revealed that
L. plantarum CIP 104448 lacks the complete plantaricin biosynthesis gene cluster (and a large
set of genes adjacent to this cluster (i.e. OGs 334-348), and the entire gene cluster
for EPS biosynthesis.
L.
plantarum TIFN 101 is missing some genes associated with plantaricin biosynthesis as well as
genes for exopolysaccharide biosynthesis, many sugar utilization cassettes, and two
large LPXTG-anchored mucus-binding proteins.
Table 2. The ten most up- and down-regulated genes in NSAID-stressed human intestine after
consumption of
L. plantarum WCFS1 (WCSF1).
| Top 10: Upregulated genes placebo versus WCFS1 |
Gene name |
IBMT p value |
Mean fold versus control |
| kinesin family member 20B |
KIF20B |
0.01 |
1.34 |
| microRNA 186 |
MIR186 |
0.03 |
1.31 |
| guanylate cyclase activator 2A (guanylin) |
GUCA2A |
0.04 |
1.31 |
| integrin, alpha 4 (antigen CD49D, alpha 4 subunit of VLA-4 receptor) |
ITGA4 |
0.01 |
1.31 |
| centromere protein E, 312kDa |
CENPE |
0.05 |
1.30 |
| putative homeodomain transcription factor 1 |
PHTF1 |
0.00 |
1.30 |
| spindle and kinetochore associated complex subunit 2 |
SKA2 |
0.01 |
1.29 |
| killer cell lectin-like receptor subfamily D, member 1 |
KLRD1 |
0.00 |
1.29 |
| gamma-aminobutyric acid (GABA) A receptor, alpha 2 |
GABRA2 |
0.02 |
1.27 |
| retinitis pigmentosa GTPase regulator |
RPGR |
0.01 |
1.27 |
| Top 10: Downregulated genes placebo versus WCFS1 |
|
|
|
| small nucleolar RNA, H/ACA box 16A |
SNORA16A |
0.02 |
-1.35 |
| small nucleolar RNA, C/D box 53 |
SNORD53 |
0.04 |
-1.36 |
| contactin 3 (plasmacytoma associated) |
CNTN3 |
0.00 |
-1.38 |
| small nucleolar RNA, C/D box 6 |
SNORD6 |
0.04 |
-1.39 |
| small nucleolar RNA, H/ACA box 57 |
SNORA57 |
0.00 |
-1.44 |
| small nucleolar RNA, H/ACA box 60 |
SNORA60 |
0.00 |
-1.44 |
| small nucleolar RNA, H/ACA box 14A |
SNORA14A |
0.03 |
-1.49 |
| small nucleolar RNA, H/ACA box 38B (retrotransposed) |
SNORA38B |
0.01 |
-1.58 |
| small nucleolar RNA, H/ACA box 14B |
SNORA14B |
0.01 |
-1.58 |
| small Cajal body-specific RNA 4 |
SNORA16A |
0.01 |
-1.72 |
Table 3. The ten most up- and down-regulated genes in NSAID-stressed human intestine after
consumption of
L. plantarum CIP104448 (CIP48).
| Top 10: Upregulated genes placebo versus CIP48 |
Gene name |
IBMT p value |
Mean fold versus control |
| coiled-coil domain containing 59 |
CCDC59 |
0.01 |
1.33 |
| aldehyde dehydrogenase 1 family, member L2 |
ALDH1L2 |
0.03 |
1.32 |
| KIAA0125 |
KIAA0125 |
0.00 |
1.31 |
| phospholipase C, beta 4 |
PLCB4 |
0.01 |
1.31 |
| coiled-coil domain containing 102B |
CCDC102B |
0.04 |
1.29 |
| RAS guanyl releasing protein 3 (calcium and DAG-regulated) |
RASGRP3 |
0.03 |
1.28 |
| peptidase domain containing associated with muscle regeneration 1 |
PAMR1 |
0.00 |
1.28 |
| DEP domain containing 1 |
DEPDC1 |
0.01 |
1.28 |
| phospholipase A2, group IIA (platelets, synovial fluid) |
PLA2G2A |
0.02 |
1.28 |
| heparan sulfate (glucosamine) 3-O-sulfotransferase 3B1 |
HS3ST3B1 |
0.04 |
1.28 |
| Top 10: Downregulated genes placebo versus CIP48 |
|
|
|
| potassium channel, subfamily K, member 15 |
KCNK15 |
0.05 |
-1.33 |
| transient receptor potential cation channel, subfamily V, member 6 |
TRPV6 |
0.01 |
-1.33 |
| long intergenic non-protein coding RNA 282 |
LINC00282 |
0.03 |
-1.35 |
| ephrin-A1 |
EFNA1 |
0.02 |
-1.38 |
| matrix metallopeptidase 10 (stromelysin 2) |
MMP10 |
0.05 |
-1.41 |
| angiopoietin-like 4 |
ANGPTL4 |
0.03 |
-1.47 |
| heme oxygenase (decycling) 1 |
HMOX1 |
0.00 |
-1.50 |
| nuclear factor, interleukin 3 regulated |
NFIL3 |
0.01 |
-1.52 |
| major facilitator superfamily domain containing 2A |
MFSD2A |
0.02 |
-1.59 |
| glucose-6-phosphatase, catalytic subunit |
G6PC |
0.02 |
-1.65 |
Table 4. The ten most up- and down-regulated genes in NSAID-stressed human intestine after
consumption of
L. plantarum TIFN 101
| Top 10: Upregulated genes placebo versus TIFN 101 |
Gene name |
IBMT p value |
Mean fold versus control |
| immunoglobulin lambda variable 6-57 |
IGLV6-57 |
0.01 |
1.63 |
| putative V-set and immunoglobulin domain-containing protein 6-like |
LOC642131 |
0.00 |
1.55 |
| immunoglobulin lambda variable 7-46 (gene/pseudogene) |
IGLV7-46 |
0.04 |
1.48 |
| heparan sulfate (glucosamine) 3-O-sulfotransferase 3B1 |
HS3ST3B1 |
0.00 |
1.41 |
| interferon regulatory factor 4 |
IRF4 |
0.00 |
1.40 |
| GDNF family receptor alpha 2 |
GFRA2 |
0.00 |
1.40 |
| CD27 molecule |
CD27 |
0.01 |
1.40 |
| CD79a molecule, immunoglobulin-associated alpha |
CD79A |
0.03 |
1.38 |
| plasminogen activator, tissue |
PLAT |
0.00 |
1.37 |
| Der1-like domain family, member 3 |
DERL3 |
0.00 |
1.37 |
| Top 10: Downregulated genes placebo versus TIFN 101 |
|
|
|
| small nucleolar RNA, H/ACA box 38B (retrotransposed) |
SNORA38B |
0.04 |
-1.40 |
| small nucleolar RNA, H/ACA box 21 |
SNORA21 |
0.03 |
-1.40 |
| small nucleolar RNA, H/ACA box 60 |
SNORA60 |
0.01 |
-1.41 |
| small nucleolar RNA, C/D box 53 |
SNORD53 |
0.01 |
-1.43 |
| ephrin-A1 |
EFNA1 |
0.00 |
-1.45 |
| small nucleolar RNA, C/D box 6 |
SNORD6 |
0.02 |
-1.46 |
| small nucleolar RNA, H/ACA box 57 |
SNORA57 |
0.00 |
-1.47 |
| small nucleolar RNA, H/ACA box 14B |
SNORA14B |
0.00 |
-1.73 |
| family with sequence similarity 5, member C |
FAM5C |
0.03 |
-1.97 |
| small Cajal body-specific RNA 4 |
SCARNA4 |
0.00 |
-2.00 |
Table 5. Summary of main unique contigs/ gene clusters/genes in
L. plantarum TIFN 101; the sequence identity numbers are depicted in column 3, the first SEQ ID
NO depicts the polynucleotide sequence, the second SEQ ID NO depicts the encoded polypeptide
[polynucleotide; polypeptide].
| OGs |
Contains functions |
SEQ ID NO: |
| chromosome |
|
|
| 185 |
MFS family transporter |
176; 260 |
| 186 |
fumarate reductase/succinate dehydrogenase flavoprotein |
177; 261 |
| 187 |
Transcriptional regulator, AraC family |
178; 262 |
| 382 |
toxin-antitoxin system, antitoxin component MazE, AbrB family |
179; 263 |
| 383 |
toxin-antitoxin system, toxin component MazF, PemK family |
180; 264 |
| 409 |
Hypothetical protein |
181; 265 |
| 410 |
Conserved ankyrin repeat protein, putative |
182; 266 |
| 411 |
integral membrane protein |
183; 267 |
| 461 |
nitrate/sulfonate/bicarbonate ABC transporter, substrate-binding protein |
184; 268 |
| 462 |
nitrate/sulfonate/bicarbonate ABC transporter, permease protein |
185; 269 |
| 463 |
nitrate/sulfonate/bicarbonate ABC transporter, ATP-binding protein |
186; 270 |
| 1197 |
ADP-ribosylglycohydrolase |
187; 271 |
| 1986 |
abortive infection bacteriophage resistance protein |
188; 272 |
| 2366 |
cell wall hydrolase, glycosyl hydrolase family 25 |
189; 273 |
| 2549 |
membrane proteinase PrsW, regulator of anti-sigma factor |
190; 274 |
| 2583 |
hypothetical membrane protein, YfhO family |
191; 275 |
| 2610 |
Fructokinase (EC 2.7.1.4) |
192; 276 |
| 2611 |
glycosyl hydrolase, family 38 |
193; 277 |
| 2612 |
PTS system, IIC component |
194; 278 |
| 2613 |
PTS system, fructose-specific IIBC component (EC 2.7.1.69) |
195; 279 |
| 2614 |
(EC 2.7.1.69) / PTS system, fructose-specific IIC component (EC 2.7.1.69) |
196; 280 |
| 2615 |
Transcription antiterminator, BglG family |
197; 281 |
| on putative plasmids |
|
|
| 3299 |
hydrolase, HD superfamily, C-terminus |
198; 282 |
| 3300 |
Ribonucleotide reduction protein NrdI |
199; 283 |
| 3301 |
Ribonucleotide reductase of class Ib (aerobic), alpha subunit (EC 1.17.4.1) |
200; 284 |
| 3302 |
Ribonucleotide reductase of class Ib (aerobic), beta subunit (EC 1.17.4.1) |
201; 285 |
| 3303 |
Ribonucleotide reductase of class Ib (aerobic), beta subunit (EC 1.17.4.1) |
202; 286 |
| 3304 |
transposase, fragment |
203; 287 |
| 3305 |
Site-specific recombinase, DNA invertase Pin related protein |
204; 288 |
| 3306 |
membrane protein with DUF161 and DUF2179 domains, YitT family |
205; 289 |
| 3307 |
Na(+)/H(+) antiporter |
206; 290 |
| 3308 |
Voltage-gated chloride channel family protein |
207; 291 |
| 3323 |
Glucose uptake protein |
208; 292 |
| 3324 |
Mannose-6-phosphate isomerase |
209; 293 |
| 3325 |
hypothetical protein, C-terminus |
210; 294 |
| 3326 |
hypothetical protein |
211; 295 |
| 3327 |
Glutamine synthetase type I (EC 6.3.1.2) |
212; 296 |
| 3328 |
transposase |
213; 297 |
| 3329 |
toxin-antitoxin system, toxin component, PemK/MazF family |
214; 298 |
| 3330 |
toxin-antitoxin system, antitoxin component, PemI/MazE family |
215; 299 |
| 3331 |
integrase/recombinase |
216; 300 |
| 3332 |
hypothetical protein, C-terminus |
217; 301 |
| 3333 |
hypothetical protein |
218; 302 |
| 3334 |
Cold shock protein CspA |
219; 303 |
| 3335 |
toxin-antitoxin system, RelE/StbE family; replication protein RepA |
220; 304 |
| 3336 |
hypothetical protein |
221; 305 |
| 3337 |
Transcriptional regulator, PBSX/Xre family |
222; 306 |
| 3338 |
hypothetical protein |
223; 307 |
| 3339 |
integrase/recombinase |
224; 308 |
| 3340 |
toxin-antitoxin system, antitoxin component, Phd_YefM family |
225; 309 |
| 3341 |
toxin-antitoxin system, toxin component, RelE/StbE family |
226; 310 |
| 3342 |
hypothetical protein |
227; 311 |
| 3343 |
hypothetical protein |
228; 312 |
| 3344 |
ISEf1, transposase |
229; 313 |
| 3345 |
hypothetical membrane protein |
230; 314 |
| 3346 |
hypothetical protein, N-terminus |
231; 315 |
| 3347 |
replication protein RepA |
232; 316 |
| 3348 |
hypothetical protein |
233; 317 |
| 3349 |
Transposase IS66 |
234; 318 |
| 3350 |
Transposase IS66, N-terminus |
235; 319 |
| 3351 |
Transposase IS66, C-terminus |
236; 320 |
| 3352 |
Pyridine nucleotide-disulfide oxidoreductase |
237; 321 |
| 3353 |
LtrC-like protein |
238; 322 |
| 3354 |
Major facilitator: Oxalate:Formate Antiporter |
239; 323 |
| 3355 |
transposase IS3/IS911 family protein |
240; 324 |
| 3356 |
Excinuclease ABC subunit A paralog |
241; 325 |
| 3357 |
site-specific recombinase |
242; 326 |
| 3358 |
Iron-sulfur cluster assembly protein SufB, permease, C-terminus |
243; 327 |
| 3359 |
membrane protein, MarC family |
244; 328 |
| 3360 |
peptidase E |
245; 329 |
| 3361 |
hypothetical protein |
246; 330 |
| 3362 |
FIG00742910: hypothetical protein |
247; 331 |
| 3363 |
alkaline shock protein, Asp23 family |
248; 332 |
| 3364 |
hypothetical membrane protein |
249; 333 |
| 3365 |
hypothetical protein |
250; 334 |
| 3366-3371 |
FIG00753329: hypothetical protein, N-terminus |
251; 335 |
| 3367 |
FIG00742586: hypothetical protein |
252; 336 |
| 3368 |
replication initiator protein, C-terminus |
253; 337 |
| 3369 |
replication initiator protein, N-terminus |
254; 338 |
| 3370 |
hypothetical protein |
255; 339 |
| 3371 |
plasmid partitioning ATPase ParA |
256; 340 |
Discussion
[0099] This study was undertaken to investigate whether
L. plantarum strains selected
in vitro for their differential immune stimulating capacity have different impact on local
and systemic immunity in healthy individuals undergoing a mild, commonly encountered
stressor of intestinal immunity. All three strains had an effect on immunity but that
this effect was highly strain dependent and may not be beneficial in certain contexts.
On the basis of results obtained by dendritic cell stimulation with
L.plantarum strains
in vitro the immune properties, of strain. WCFS1 was considered to be proinflammatory,
L. plantarum CIP104448 as neutral and
L. plantarum TIFN 101 as regulatory. However, the immune responses to these strains
in vivo was very different to that predicted
in vitro. Consumption of NSAID induced reduction in CD4+/Foxp3 regulatory cells but was prevented
by WCFS1 and TIFN 101 administration which should be considered to be a beneficial
regulatory effect. CIP48 did not prevent NSAID induced reduction of CD4+Foxp3 T cells
and had more negative effects. CIP48 reduced the number of memory cells suggesting
a proinflammatory, worsening effect of consumption of this bacterium.
[0100] T-cell polarization was studied after different stimuli to gain insight into the
mechanisms by which bacteria might influence immunity. A hypothesis we had was that
bacterial wall components might induce immune responses (Smelt et al., 2012) and enhance
systemic immunity as bystander effect. However, this hypothesis had to be rejected
as the sole responsible mechanism as only WCFS1 showed a trend of elevation of IL17
production after challenging whole blood of the WCSF1 consumers with the bacterial
strain. The most pronounced stimulator of immunity, i.e. TIFN 101, showed no response
to the bacterial extract but enhanced the responses against specific pathogenic antigens
such as SEB and that against TT.
[0101] The analysis of the mucosal transcriptome suggested that the enhanced memory response
is related to TIFN 101 enhanced upregulation of processes associated with T- and B-cell
function and antigen presentation. TIFN 101 in contrast to the other bacteria had
a pronounced effect on immunological related pathways in the mucosa of the consumers.
In particular TIFN 101 enhanced pathways and genes related to antigen presentation.
TIFN 101 had a pronounced effect on CD27 upregulation which is required for generation
and long-term maintenance of T cell immunity (Huang et al., 2013). Also TIFN 101 enhanced
the expression of MHC-II α in mucosa and of key regulatory molecules such as RAPL.
RAPL enhances integrin affinity and the adhesion of T-cells (Raab et al., 2010; Zhang
and Wang, 2012). These observations in the mucosa may explain the enhanced memory
T-cell responses observed in the TIFN 101 consumers. Also B-cell immunity in the mucosa
was enhanced as illustrated by upregulation of immunoglobulin regulatory genes and
by CD79a. CD79A is also known as B-cell antigen receptor complex-associated protein
alpha chain forming together with CD79b protein the B-cell antigen receptor (Herren
and Burrows, 2002). CIP48 and WCFS1 did not have these effects or downregulated processes
such as antigen presentation in the mucosa. The observation that bacteria can downregulate
snoRNAs in the intestine has to our best knowledge not been reported before. SnoRNA
are metabolically stable noncoding RNAs that associate with a set of proteins to form
small nucleolar RNPs (snoRNPs). The majority of snoRNA function as guide RNAs in the
post-transcriptional synthesis of 2'-O-methylated nucleotides and pseudouridines in
rRNAs, small nuclear RNAs (snRNAs) and other cellular RNAs, including mRNAs (Bratkovic
and Rogelj, 2011; Esteller, 2011; Williams and Farzaneh, 2012). The relative reduction
in snoRNA 53, 57, 60 by CIP48 and WCFS1 suggest a downregulation of methylation of
ribosomal RNA (Kiss-Laszlo et al., 1996) and downregulation of 14b diminished pseudouridinilation
of RNA (Kiss et al., 2004). Usually this suggest a destabilization of cellular processes
(Su et al., 2014), again suggesting that CIP48 and WCFS1 are not beneficial for a
mildly stressed intestinal environment.
[0102] We applied genome sequencing of
L. plantarum CIP 104448 and
L. plantarum TIFN 101 to identify possible gene clusters that might be responsible for the differential
biological effects of the three
L. plantarum strains. Several hundred novel
L. plantarum genes were found in strain CIP48 (340 new OGs) and TIFN 101 (177 OGs) compared to
strain WCFS1. Only a small number of these (47 OGs) are shared by both CIP48 and TIFN
101. The majority of these novel genes appear to be on plasmids.
L. plantarum TIFN 101 partly lacks the plantaricin biosynthesis clusters. These genes have in
previous studies been linked to strain differences in cytokine production (Meijerink
et al., 2010; Wells et al., 2011) but were shown here not to be associated with immune
effects
in vivo. Also
L. plantarum CIP104448 and
L. plantarum TIFN 101 lack very large regions of the sugar metabolism. These adaptations have
been attributed to adaptations to environmental factors which are interesting targets
to identify genes associated with probiotic effects (Molenaar et al., 2005). Not only
presence but also absence of genes may enhance immune effects of bacteria (Smelt et
al., 2013b). This comparative genomics study in which effects of
L. plantarum supplementation on the mucosal transcriptome were combined with systemic immune activation
parameters provides many leads for follow-up experimental work to identify genes that
are responsible for or involved in the observed differences in immune effects in the
human subject.
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